1. Field of the Invention
The present invention relates to a wheel chair, and more particularly to a wheel chair having a foldable back support rotatable or adjustable relative to a supporting base frame of the wheel chair to various angular positions.
2. Description of the Prior Art
Typical wheel chairs comprise a supporting base frame for supporting users thereon, and a pair of handles attached to a back support of the base frame, for moving or operating the wheel chair. Normally, the back support is solidly extended from or formed integral with the base frame and thus may not be adjusted relative to the base frame to different angular positions.
For example, U.S. Pat. No. 5,199,520 to Chen discloses one of the typical wheel chairs including a back support solidly secured to or formed integral with the base frame, such that the back support may not be adjusted relative to the base frame to different angular positions.
U.S. Pat. No. 4,339,013 to Weigt discloses another typical wheel chair including a back support foldably secured or attached to a base frame together with a padded support. However, the back support may only be folded relative to the base frame to either a seating position that is perpendicular to a seat, or a laying position that is parallel to the seat, such that the back support also may not be adjusted relative to the base frame to different angular positions.
U.S. Pat. No. 5,560,636 to Chen discloses a further typical wheel chair including a rotatable seat portion and back support and foot support that may be folded or rotated to a substantially vertical position, for helping patients to stand up. However, similarly, the back support also may not be adjusted relative to the base frame to different angular positions.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional wheel chairs.